What is the minimum number of blood parts
needed for open-heart surgery?

Explanation:

During perfusion, 29 patients (12%) received 34 units of blood in the pump-oxygenator, and after bypass 64 patients (27%) received 65 units of blood in the operating room (average intraoperative use, 203 ml per patient). For the total hospital stay, the blood requirement was 728 ml per patient.

the answer that best describes the relative refractory period in the neuron is the resting membrane potential is restored, but concentrations of sodium and potassium are not restored to their original state.

the refractory period is the time during which another stimulus given to the neuron will not lead to a second potential. thus, because na+ channels are inactivated during this time, additional depolarizing stimuli do not lead to new action potentials.  

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